Indicia reading devices (also referred to as optical indicia readers, scanners, RFID readers, etc.) typically read indicia data represented by printed indicia or data carrier indicia, (also referred to as symbols, symbology, bar codes, RFID tags, etc.) For instance one type of a symbol is an array of rectangular bars and spaces that are arranged in a specific way to represent elements of data in machine readable form. Another type of symbol is encoded as data in an RFID tag. Optical indicia reading devices typically transmit light onto a symbol and receive light scattered and/or reflected back from a bar code symbol. The received light is interpreted by an image processor to extract the data represented by the symbol. Laser indicia reading devices typically utilize transmitted laser light. RFID readers typically activate RFID tags which transmit data symbols to the RFID readers.
One-dimensional (1D) optical bar code readers are characterized by reading data that is encoded along a single axis, in the widths of bars and spaces, so that such symbols can be read from a single scan along that axis, provided that the symbol is imaged with a sufficiently high resolution along that axis.
In order to allow the encoding of larger amounts of data in a single bar code symbol, a number of 1D stacked bar code symbologies have been developed which partition encoded data into multiple rows, each including a respective 1D bar code pattern, all or most all of which must be scanned and decoded, then linked together to form a complete message. Scanning still requires relatively higher resolution in one dimension only, but multiple linear scans are needed to read the whole symbol.
A class of bar code symbologies known as two dimensional (2D) matrix symbologies have been developed which offer orientation-free scanning and greater data densities and capacities than 1D symbologies. 2D matrix codes encode data as dark or light data elements within a regular polygonal matrix, accompanied by graphical finder, orientation and reference structures.
Conventionally, an indicia reader, whether portable or otherwise, optical or wireless, may include a central processor which directly controls the operations of the various electrical components housed within the indicia reader. For example, the central processor controls detection of keyboard entries, display features, trigger detection, and indicia read and decode functionality.
Efforts regarding such systems have led to continuing developments to improve their versatility, practicality and efficiency.